Submission #491860

#	Time	Username	Problem	Language	Result	Execution time	Memory
491860		ValiAntonie	Fancy Fence (CEOI20_fancyfence)	C++14	12 / 100	50 ms	1000 KiB

fancyfence

#include <bits/stdc++.h>

using namespace std;

stack <pair<int,int>> S;
long long n,v[100005],i,dr[100005],st[100005],x,suma[100001],mars[100001],j,val,Max[100005];
pair <int,int> sor[100005];
long long total;
#define mod 1000000007
long long rectCount(long long n, long long m)
{
    return ((((m % 1000000007 * n % 1000000007) % 1000000007 * (n + 1) % 1000000007) % 1000000007 * (m + 1) % 1000000007) % 1000000007)/ 4;
}


int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cin>>n;
for(i=1;i<=n;i++){
    cin>>v[i];
    sor[i].first = v[i];
    sor[i].second = i;
}
sort(sor+1,sor+n+1);
for(i=1;i<=n;i++){
    cin>>x;
    suma[i] = suma[i-1] + x;
}
for(i=1;i<=n;i++){
    x = v[i];
    while(S.empty() == false && x<S.top().first){
        dr[S.top().second] = i;
        S.pop();
    }
    S.push({x,i});
}
while(S.empty() == false){
    S.pop();
}
for(i=n;i>=1;i--){
    x = v[i];
    while(S.empty() == false && x < S.top().first){
        st[S.top().second] = i;
        S.pop();
    }
    S.push({x,i});
}
for(i=1;i<=n;i++){
    if(!dr[i])
    dr[i] = n + 1;
}
for(i=1;i<=n;i++){
    total += rectCount(suma[dr[sor[i].second]-1] - suma[st[sor[i].second]],sor[i].first) % 1000000007;
    total -= rectCount(suma[dr[sor[i].second]-1] - suma[st[sor[i].second]],Max[sor[i].second]) % 1000000007;
    for(j=st[sor[i].second];j<=dr[sor[i].second];j++){
        Max[j] = sor[i].first;
    }
}
cout << total % 1000000007;
    return 0;
}

• Subtask 1: 0 / 0
• Subtask 2: 12 / 12
• Subtask 3: 0 / 13
• Subtask 4: 0 / 15
• Subtask 5: 0 / 15
• Subtask 6: 0 / 18
• Subtask 7: 0 / 27